The need for treating sewage sludge for disposal, and particularly municipal sewage sludge, has increased substantially in recent years. One way of dosing so, is by mixing or blending alkaline materials with the sludge. There is also developing an increasing demand, particularly with respect to municipal sewage sludge, that the treatment of the sludge be sufficiently thorough that is will allow beneficial re-use of sludge, such as enabling the sludge to be applied to land on which agricultural and ornamental corps may be grown. One way of doing so is to mix alkaline products with sludge in a manner that blends the alkaline and sludge.
When sewage sludge is only treated with an alkaline material such as lime, without a sufficient increase in sludge temperature, the resulting mix may be only partially stabilized, such that higher pathogenic organisms are not destroyed.
In the treatment of sewage sludge, such can produce dust as a result of the treatment process and odors, and steam can result from the temperature reached during the treatment process. Additionally, ammonia can be produced during the treatment process.
Additionally, the use of lime during the treatment process can results in build-up of scale resultant from the lime treatment on surfaces that are exposed to the lime treatment.